JJY
JJY is the call sign of a low frequency time signal radio station located in Japan. The station broadcasts from two sites, one on Mount Otakadoya, near Fukushima, and the other on Mount Hagane, located on Kyushu island. JJY is operated by the National Institute of Information and Communications Technology (NICT), an independent administrative institution affiliated with the Ministry of Internal Affairs and Communications of the Japanese government. Transmission sites The Mount Otakadoya site () is located at an elevation of 790 meters (2,590 ft) in Tamura City, Fukushima Prefecture. It broadcasts a 50 kW signal (13 kW ERP) on 40 kHz from an umbrella top-loading antenna situated 250 meters (820 ft) above the ground. In March 2011, it was powered down and evacuated due to its proximity to the Fukushima Daiichi nuclear disaster. It resumed broadcasting on April 21, unattended by staff. It went off air again temporarily on April 25 due to lightning, but has ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Haganeyama Transmitter
is an Low frequency, LF-time signal transmitter at Fuji-cho, Saga (city), Saga-city, Saga Prefecture, Saga-ken, Japan used for transmitting the time signal JJY on 60 kHz. The Haganeyama site is one of two JJY transmitters, another is the Otakadoyayama Transmitter, Otakadoyama site. Summary Source: * NAME: National Institute of Information and Communications Technology, NICT Haganeyama LF station * Location: Summit of Mt. Hagane, Fuji-cho, Saga (city), Saga-city, Saga Prefecture, Saga-ken * Elevation: about 900m * Latitude: 33°27'56.0"N * Longitude: 130°10'32.0"E * License: National Institute of Information and Communications Technology, NICT * Station purpose: Transmitting the official Japanese government frequency standards and time signal * Types of radio emissions, Frequency form: 250H A1B * Radio frequency, Frequency: 60Hertz, kHz * Transmitter power output, Antenna power: 50Watt, kW (Antenna efficiency: about 45%) * Antenna form: Umbrella type 200m high * Operation ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Tamura, Fukushima
is a city located in Fukushima Prefecture, Japan. , the city had an estimated population of 35,702 in 12,821 households and a population density of 78 persons per km². The total area of the city was . Geography Tamura is located in east-central Fukushima Prefecture, in the easternmost portion of the Nakadōri region of then prefecture. The town is located in a hilly region of the Abukuma Mountains. Neighboring municipalities * Fukushima Prefecture ** Iwaki ** Katsurao ** Kawauchi **Kōriyama ** Miharu **Namie ** Nihonmatsu ** Ōkuma ** Ono Climate Tamura has a humid continental climate (Köppen ''Cfa'') characterized by mild summers and cold winters with heavy snowfall. The average annual temperature in Tamura is 10.4 °C. The average annual rainfall is 1368 mm with September as the wettest month. The temperatures are highest on average in August, at around 23.1 °C, and lowest in January, at around -0.1 °C. Demographics Per Japanese census data, the p ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Low Frequency
Low frequency (LF) is the ITU designation for radio frequencies (RF) in the range of 30–300 kHz. Since its wavelengths range from 10–1 km, respectively, it is also known as the kilometre band or kilometre waves. LF radio waves exhibit low signal attenuation, making them suitable for long-distance communications. In Europe and areas of Northern Africa and Asia, part of the LF spectrum is used for AM broadcasting as the "longwave" band. In the western hemisphere, its main use is for aircraft beacons, navigation (LORAN, mostly defunct), information, and weather systems. A number of time signal broadcasts also use this band. The main mode of transmission used in this band is ground waves, in which LF radio waves travel just above the Earth's surface, following the terrain. LF ground waves can travel over hills, and can travel far beyond the horizon, up to several hundred kilometers from the transmitter. Propagation Because of their long wavelength, low frequen ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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National Institute Of Information And Communications Technology
The is Japan's primary national research institute for information and communications. It is located in Koganei, Tokyo, Japan. NICT was established as an Independent Administrative Institution in 2004 when Japan's Communications Research Laboratory (established 1896) merged with the Telecommunications Advancement Organization. Today NICT's mission is to carry out research and development in the field of information and communications technology. It has a range of responsibilities including generating and disseminating Japan's national frequency and time standards; conducting type approval tests of radio equipment for the Global Maritime Distress Safety System (GMDSS) and marine radar based on Japan's Radio Law; and providing regular observations of the ionosphere and space weather. It also operates the JJY, a low frequency time signal. In late August 2015, it was announced that a terahertz radiation scanner developed by the institute would be one of the instruments carried b ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Japan Standard Time
, or , is the standard time zone in Japan, 9 hours ahead of UTC (UTC+09:00). Japan does not observe daylight saving time, though its introduction has been debated on several occasions. During World War II, the time zone was often referred to as Tokyo Standard Time. Japan Standard Time is equivalent to Time in South Korea, Korean Standard Time, Time in North Korea, Pyongyang Time (North Korea), Time in Indonesia, Eastern Indonesia Standard Time, Time in East Timor, East-Timorese Standard Time, Time in Palau, Palau Time, and Yakutsk Time (Russia). History Before the Meiji (era), Meiji era (1868–1912), each local region had its own time zone in which noon was when the sun was exactly at its culmination. As modern transportation methods, such as trains, were adopted, this practice became a source of confusion. For example, there is a difference of about 5 degrees longitude between Tokyo and Osaka and because of this, a train that departed from Tokyo would arrive at Osaka 20 minu ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Low Frequency
Low frequency (LF) is the ITU designation for radio frequencies (RF) in the range of 30–300 kHz. Since its wavelengths range from 10–1 km, respectively, it is also known as the kilometre band or kilometre waves. LF radio waves exhibit low signal attenuation, making them suitable for long-distance communications. In Europe and areas of Northern Africa and Asia, part of the LF spectrum is used for AM broadcasting as the "longwave" band. In the western hemisphere, its main use is for aircraft beacons, navigation (LORAN, mostly defunct), information, and weather systems. A number of time signal broadcasts also use this band. The main mode of transmission used in this band is ground waves, in which LF radio waves travel just above the Earth's surface, following the terrain. LF ground waves can travel over hills, and can travel far beyond the horizon, up to several hundred kilometers from the transmitter. Propagation Because of their long wavelength, low frequen ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Carrier Wave
In telecommunications, a carrier wave, carrier signal, or just carrier, is a periodic waveform (usually sinusoidal) that conveys information through a process called ''modulation''. One or more of the wave's properties, such as amplitude or frequency, are modified by an information bearing signal, called the ''message signal'' or ''modulation signal''. The carrier frequency is usually much higher than the message signal frequency; this is because it is usually impractical to transmit signals with low frequencies over long distances (due to attenuation). The purpose of the carrier is usually either to transmit the information through space as an electromagnetic wave (as in radio communication), or to allow several carriers at different frequencies to share a common physical transmission medium by frequency division multiplexing (as in a cable television system). The term originated in radio communication, where the carrier wave creates the waves which carry the information (mod ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Antenna (radio)
In radio-frequency engineering, an antenna (American English) or aerial (British English) is an electronic device that converts an alternating current, alternating electric current into radio waves (transmitting), or radio waves into an electric current (receiving). It is the interface between radio waves Radio propagation, propagating through space and electric currents moving in metal Electrical conductor, conductors, used with a transmitter or receiver (radio), receiver. In transmission (telecommunications), transmission, a radio transmitter supplies an electric current to the antenna's Terminal (electronics), terminals, and the antenna radiates the energy from the current as electromagnetic radiation, electromagnetic waves (radio waves). In receiver (radio), reception, an antenna intercepts some of the power of a radio wave in order to produce an electric current at its terminals, that is applied to a receiver to be amplifier, amplified. Antennas are essential components ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Fukushima Daiichi Nuclear Disaster
The Fukushima nuclear accident was a major nuclear accident at the Fukushima Daiichi Nuclear Power Plant in Ōkuma, Fukushima, Japan, which began on 11 March 2011. The cause of the accident was the 2011 Tōhoku earthquake and tsunami, which resulted in electrical grid failure and damaged nearly all of the power plant's Emergency power system, backup energy sources. The subsequent inability to sufficiently cool reactors after shutdown compromised Primary containment, containment and resulted in the release of radioactive contamination, radioactive contaminants into the surrounding environment. The accident was rated seven (the maximum severity) on the International Nuclear Event Scale by Nuclear and Industrial Safety Agency, following a report by the JNES (Japan Nuclear Energy Safety Organization). It is regarded as the worst nuclear incident since the Chernobyl disaster in 1986, which was also rated a seven on the International Nuclear Event Scale. According to the United Nati ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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PC Magazine
''PC Magazine'' (shortened as ''PCMag'') is an American computer magazine published by Ziff Davis. A print edition was published from 1982 to January 2009. Publication of online editions started in late 1994 and continues . Overview ''PC Magazine'' provides reviews and previews of the latest hardware and software for the information technology professional. Other regular departments include columns by long-time editor-in-chief Michael J. Miller ("Forward Thinking"), Bill Machrone, and Jim Louderback, as well as: * "First Looks" (a collection of reviews of newly released products) * "Pipeline" (a collection of short articles and snippets on computer-industry developments) * "Solutions" (which includes various how-to articles) * "User-to-User" (a section in which the magazine's experts answer user-submitted questions) * "After Hours" (a section about various computer entertainment products; the designation "After Hours" is a legacy of the magazine's traditional orientation to ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Blue Pog
Blue is one of the three primary colours in the RYB color model, RYB colour model (traditional colour theory), as well as in the RGB color model, RGB (additive) colour model. It lies between Violet (color), violet and cyan on the optical spectrum, spectrum of visible light. The term ''blue'' generally describes colours perceived by humans observing light with a dominant wavelength that's between approximately 450 and 495 nanometres. Most blues contain a slight mixture of other colours; Azure (color), azure contains some green, while ultramarine contains some violet. The clear daytime sky and the deep sea appear blue because of an optical effect known as Rayleigh scattering#Cause of the blue colour of the sky, Rayleigh scattering. An optical effect called the Tyndall effect explains Eye color#Blue, blue eyes. Distant objects appear more blue because of another optical effect called aerial perspective. Blue has been an important colour in art and decoration since ancient t ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Pulse-width Modulation
Pulse-width modulation (PWM), also known as pulse-duration modulation (PDM) or pulse-length modulation (PLM), is any method of representing a signal as a rectangular wave with a varying duty cycle (and for some methods also a varying period). PWM is useful for controlling the average power or amplitude delivered by an electrical signal. The average value of voltage (and current) fed to the load is controlled by switching the supply between 0 and 100% at a rate faster than it takes the load to change significantly. The longer the switch is on, the higher the total power supplied to the load. Along with maximum power point tracking (MPPT), it is one of the primary methods of controlling the output of solar panels to that which can be utilized by a battery. PWM is particularly suited for running inertial loads such as motors, which are not as easily affected by this discrete switching. The goal of PWM is to control a load; however, the PWM switching frequency must be sele ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |